In order to seal blood vessels during surgery, for the purpose of defunctionalizing the vessels or to halt or prevent bleeding, radiofrequency (RF) energy can be applied to the vessel structure instead of staples or clips. Traditionally, forceps are used to create a single seal per application with bipolar RF energy. Normally, forceps that have a hinge between the tines that press against either side of the vessel are camped about tissue and power is applied. Problems are sometimes encountered with this technique because of the forceps bending or the lack of parallelism between the tines thus affecting how the tissue or vessel is compressed and sealed.
U.S. Pat. No. 5,585,896 has a percutaneous device for sealing openings in blood vessels. A balloon is inserted into the vessel and then inflated to force the vessel wall into a fixation collar.
U.S. Pat. No. 5,383,897 has a device for sealing punctures in blood vessels by conforming to the inner lumen of the vessel and placing barbs in the vessel for the purpose of sealing.
U.S. Pat. No. 5,391,183 has a device for sealing punctures in vessels by inserting hemostatic material into the puncture site and around the outside of the vessel, for the purpose of closing the puncture site.
U.S. Pat. No. 5,437,292 has a percutaneous device to seal arterial or venous puncture sites, whether accidental or intentional, which mixes fibrinogen and thrombin to form a gel around the puncture site to provide occlusion.
U.S. Pat. No. 5,411,520 has a device for percutaneously sealing blood vessels that slides down a holding catheter and enters the blood vessel with an anchor and collagen plug.
U.S. Pat. No. 5,415,657 has a device that approaches the puncture in the blood vessel, engages the outer surface and applies energy to provide hemostasis.
U.S. Pat. No. 5,429,616 has a device for sealing punctures in vessels by applying a fluid and then compressing the edges while it seals.
U.S. Pat. No. 5,441,517 has a system for sealing punctures in blood vessels by mechanically inserting a plug with an anchor to seal the puncture.
U.S. Pat. No. 5,425,739 discloses a stent placed inside the vessel to seal it or placed in such a way as to anastomose the vessel edges.
U.S. Pat. No. 5,354,271 discloses a sliding sheath for closing puncture sites that has two parts that expand radially outward and may use an accordion shape if a catheter.
U.S. Pat. No. 5,342,393 is a device that repairs punctures in vessels by clamping the tissue from both inside and outside of the vessel. Riveting is used to close the clamped sections and heat may be applied to separate the rivet from the delivery system. This device does apply heat en but only to separate the rivet from the closure site.
U.S. Pat. No. 5,176,695 is a monopolar laparoscopic mechanical cutting device with a linear reciprocating blade that sharply cuts tissue residing in its slot. The present bipolar invention does not contain a sharp blade since it seals and cuts using RF energy.
U.S. Pat. No. 3,862,630 is a device wherein ultrasonic energy is used to close off blood vessels by mechanical vibration and frictional rubbing. Any heating of the tissue is a minimal and superficial byproduct of the mechanical vibration used to seal vessels.
U.S. Pat. No. 2,011,169 is a surgical electrode with end jaws that are U-shaped and nest one inside the other. They are not insulated from each other and thus are monopolar. In the present invention the jaws are insulated and bipolar. The jaws of '169 are mounted on an endoscope. They do not fit together as in the present invention and are designed more for the purpose of removing bites out of tissue and coagulating at the same time.
All of the above devices are different from the disclosure herein for several reasons. These devices are made for wound puncture closure. This implies that a viable flow channel will remain within the lumen of the blood vessel after each device is applied. The device now disclosed remains external to the blood vessel where no puncture site would normally exist either before or after the procedure. The present device and method seals the blood vessel, and thus does not provide a pathway for blood as do the prior devices discussed. In most cases, after the sealing with the instant device and method, the vessel will still be intact, although with a seal across it. In addition, the mere clamping by the disclosed device does not seal the blood vessel. It is the application of RF energy that forms an autologous clamp causing a fusion of the intima to provide the seal.
Therefore to solve the difficulties of the prior devices a patient contacting instrument for holding and applying electrosurgical energy is shown and described. During surgical dissection, blood vessels are frequently encountered that need to be sealed and thus defunctionalized. To do this in a safe, reliable manner so the vessel is properly sealed and will not leak, a tool that applies energy to create an autologous clip is valuable and required. The device and method are briefly described. A long tube connects to one side of a bipolar power supply. The tube moves longitudinally, that is along its long axis to meet against and compress the vessel with an endpiece. The two pieces that meet on either side of the vessel could be flat, curved, triangular, angled, notched, or other shapes, as long as one fits the other. If the endpieces are of some shape other than flat, this increases the surface area that traverses the vessel creating a longer seal in the vessel without increasing the diameter of the end pieces. An applied pulse of RF power cuts the tissue after sealing. The device and method when tested on fresh vessels produced a burst pressure adequate to prove a solid seal.
Advantages of the current device and method are the parallel axial closure of the end pieces to provide a compact bipolar sealer and prevent shorting. An in-line force transducer could provide feedback information on the applied force used during surgery. The device is bipolar to assure added safety by confinement of RF current flow through the tissue between the bipolar electrodes at the end of the device.